code: def forward(self, x):
      out = self.preproc(x)
      out = self.conv(out)
      out = self.postproc(out)
      return out
  
imports: import torch
  import torch.nn
label_desc: Use image node_id 2 for calling the ConvBranch obj's underlying member method code with example usage: obj.forward(x) and returns: out